


Falls Tale: The Beginning

by sporkz



Series: Falls Tale [2]
Category: Gravity Falls
Genre: Gen, Mild Violence (???), Near Death Experiences, Undertale AU (of sorts), they get a bit of bruising and a few scratches but other than they're good
Language: English
Status: Completed
Published: 2015-11-19
Updated: 2015-11-22
Packaged: 2018-05-02 09:57:46
Rating: Teen And Up Audiences
Warnings: No Archive Warnings Apply
Chapters: 2
Words: 3,183
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/5244071
Author URL: https://archiveofourown.org/users/sporkz/pseuds/sporkz
Summary: <blockquote class="userstuff">
              <p>Dipper and Mabel embark on an adventure to explore the 'Falls Valley', rumoured to be a cursed place of no return. They are supposed to return by sundown but things don't go according to that plan...</p>
            </blockquote>





	1. The Falls Valley

**Author's Note:**

> Not sure if anyone who might read this would want warnings, but I'll just say this chapter has water-related injuries/incidents with water and swimming (can you tell I'm trying not to spoil my own fic), if that kind of stuff is something you want to avoid proceed with caution. It's nothing majorly traumatic but, y'know, better safe than sorry. Enjoy!

 The Falls Valley; or 'The Valley of No Return' as the locals called it; had always captivated the two children. Their village sat atop a forested hill overlooking the gentle decline, and the first thing they saw every morning was the view of the valley from their bedroom window. Like many children the siblings had heard the legend of monsters lurking within the valley, however this strengthened their curiosities even more. Their mother dismissed their interests as the usual imagination of children, allowing her son to sketch drawings of terrible creatures whilst her daughter excitedly spoke of finding these creatures in the valley. As a mother, she always kept her eyes trained on her children and found they would play around the woods near their house but never further. Her sweet Mabel would always come back to get her chosen sweater of the day repaired after wear and tear, and her Little Dipper would amble along beside her caked in dirt, complaining when she insisted he take a bath. Their summer vacation saw this become routine, only with every passing day the twins would be absent for slightly longer, finding new trails and adventures in the woods.

 

One fateful day, Dipper and Mabel wandered until the valley was at their feet and their house was barely visible from the hill above.

"We should have lunch, bro-bro!" Mabel declared, slinging off her backpack and rummaging around for the lunch their mother packed for her.

"We could go into the valley, it's not that far," her brother commented, eyeing the overgrown path leading down to the valley and beginning to calculate how far they could explore before they missed their curfew. Mabel found a tree stump to sit upon and let her brother stare wistfully at the landscape ahead whilst she ate a sandwich.

"Mom wants us back by sunset, remember?" she said, spraying crumbs everywhere.

"I know, I know," Dipper replied, though his mind was occupied with mapping out an adventure that couldn't be condensed into a few hours.

Mabel hopped off the tree stump, reading her brother wanted to descend down the beaten path rather than sit around eating, "c'mon, navigator!" she enthusiastically slapped his back with her free hand, before taking another bite of her sandwich and following a beaming Dipper.

 

They walked aimlessly, finding the valley slightly disappointing. The trees looked the same as the ones in their woods and the ground showed no sign of beastly prints. The only difference was the sound of flowing water that grew louder as they walked.

"You haven't eaten anything yet!" Mabel suddenly realised after her brother's stomach let out a loud grumble.

"Oh, right," Dipper chuckled back, "I forgot," he dug into his own backpack and took an apple from it.

"What would you do without me, Dip-Dop?" they both laughed, then Mabel hummed and looked around for the source of the gushing sound of water.

"'think it'sh tha' way," Dipper nodded towards their left, speaking with his mouth full. The twins found a sense of freedom exploring the woods, with no mother to scold them for bad manners.

"Let's find out!" there was no mother to scold them for trampling through brambles, either, so the twins had little trouble in searching for the source of the noise.

 

The sound grew louder as the brambles grew thicker, and as the sound grew the twins became more curious. So curious, in fact, that they didn't take notice of the slowly descending sun that started to leave streaks of red in the sky.

"It must be a strong current to sound this loud!" Dipper spoke over the sound, stumbling forward for a brief moment and bumping into his sister, who was leading their expedition.

"It could be a waterfall!" Mabel excitedly replied.

 

The closer they reached the sound, the more Mabel's theory sounded true. She peeked through the twigs and leaves to find they had reached a small muddy bank overlooking a river. She stopped, her brother a few steps away from her. Before she could say anything, he approached closer but tripped on his own shoelaces. His arms flailed in an attempt to break his landing, pushing Mabel forward in the process. Mabel let out a yelp of surprise, arms also moving about to hope they landed on the ground before anything else. Unlike her brother, however, she found no landing and tumbled straight off the small ledge and into the gushing water below.

 

Her immediate reaction was a shriek from the cold water, further alerting Dipper who had taken a moment to process the situation before him.

"Mabel?!" Dipper scrambled to his feet, barely hesitating before jumping into the water after his sister. Mabel spluttered in response, her arms waving at him in warning of the strong current that was sweeping them downstream. Dipper kicked his legs wildly to reach her side of the river, however the water was considerably deep and fast-flowing for any mere human to keep afloat and he soon found himself sinking beneath the surface.

 

Mabel clung onto a thin root from a tree that had stretched over the stream of water and tried to resist peeking at the series of sharp drops the current was attempting to send her towards. The water had tucked her safely towards this spot and she had taken the opportunity. Her instincts, for a split moment, urged her to look behind her and when she indulged in this feeling she saw Dipper's hand disappear beneath the water.

"Dipper!" she called for him and felt filled with a sense of dread as the water carried her brother farther and father away, "oh no... no..." she shook her head violently, looking between her lifeline and her sibling. A part of her hoped he would resurface and muster the strength to swim over to her, but the alternative; and more likely; outcome had her sucking in a deep breath before letting go of the branch. Her thoughts were frantic as the water carried her towards her brother. She had lost Dipper many times: in the bustling market, in her haste to catch up with friends when walking to school, even at their house she often looked up to find he had wandered off. This could not compare. There was no sign of him, and every second of his absence felt like a step closer to never seeing him again.

"Dipper!" she tried calling out, being met with a mouthful of water from spending her energy away from keeping afloat. The water seemed to slope downwards unnaturally; as if it was a deep water slide; but thankfully the current had guided her away from the high drops she had seen. The sloped river continued until Mabel saw, in her frantic searching for Dipper, a rocky jaw swallow them into darkness.

 

The current almost instantly fell into a less strong ebb. Mabel didn't need to battle it, she merely needed to stay afloat.

"Dipper!" she tried again, her exhausted voice echoing in the darkness.

"Mabel?" a faint voice replied, echoing back with his own weary tone. Relief washed over her, only to be replaced by fear at the sound of rushing water intensify. Her fear grew even stronger when she heard her brother yell, followed by a dull splash seconds later. Her eyes closed as the current picked up once again: Mabel Pines had prayed for survival, whilst Dipper Pines had braced himself to die.

 

Dipper awaited her at the bottom of the drop, slumped over a rock in the enormous pool the water fell into. He caught his breath, then looked up at the strange glistening cave he found himself within. There were hundreds of softly glowing crystals which stuck out of the cracks in the rock as if they were a parasitic plant, bathing the pool in a yellow glow. At the far end of the pool there were larger crystals and land, which from the distance Dipper was observing from didn't seem to lead anywhere. Mabel soon fell into the pool, and when Dipper turned to look for her she emerged from the water coughing.

"Mabel, are you okay?!" he slid off the rock and dragged himself towards her, putting his hand on her soaked sweater sleeve. His stomach lurched at the drops of blood on the torn sweater.

"A bit scratched but okay," she shivered, "are you?"

Dipper nodded, ignoring the searing pain in his chest and limbs, "yeah," and they both let out exhausted sighs. Then Mabel stared at the glowing crystals in awe.

"I don't know where we are, but I don't like it," Dipper frowned, "no going back the way we came, though."

Mabel chewed on her bottom lip, "is that land over there? I don't wanna be in the water any more."

Dipper looked over to where Mabel was eyeing, shuddering at the sight of the jagged crystals erupting from the ground.

"I don't either, c'mon," the pair swam, weary from their ordeal and their injuries, up to the other side of the pool. The crystals stood waiting and the twins paid extra attention to not cut their hands on the sharp material as they crawled out of the water. They both winced, their skin bruised from their ordeal.

"You still have your backpack?" Mabel noticed, letting out a disbelieving laugh.

"Yeah, what happened to yours?" Dipper peeled off the soggy backpack, finding its contents were as water-logged as the rest of his belongings. He eyed the ruined detective book with a disappointed sigh: a part of him had hoped the book would survive for him to read the ending.

"I dunno, bro-bro," Mabel pulled a face as she attempted to get out of her sweater, and when she was victorious she wrung the water out of it into the pool along with her hair, "I lost my headband too!"

"I lost my hat," Dipper replied simply, though upon speaking he begun to feel like his hat was a bigger loss than he would admit.

"But we didn't lose our lives," Mabel put a hand over the star on her t-shirt, attempting to speak solemnly.

"This is all my fault," Dipper frowned, drawing his knees to his chest.

"It isn't, Dip," in an instance, Mabel sat beside him, "we'll find a way out of this!" then she smiled reassuringly.

"Yeah," Dipper meekly replied, "but where do we go first?" upon speaking those words, a bright glow shone behind them and they turned away from the pool to find a stone door illuminated by crystals.

"Through there, I guess!" Mabel's face was lit up with a sudden hope at some sense of guidance, whilst Dipper stared at the crystals with a sudden distrust.


	2. Gleaming Crystals and The Old Wizard

**Summary for the Chapter:**

> A single eye watches the twins, ready to make a deal with them in order to 'save' them from the world of the underground.

The stone door before them was engraved with a large eye, with a hastily added scratch struck across as if the perpetrator had attempted to blind it. It was surprisingly lightweight and the twins managed to push open the door with their weary combined strength. As they opened the door, the crystals surrounding them glowed faintly and both twins felt a small nagging feeling in their minds. A feeling that enticed them to rush through the door and onto a strange circular platform surrounded by smell jagged crystals.

"Dipper," Mabel nervously spoke up, "do you feel like...?" she trailed off, holding her damp sweater to her chest.

"... we're being watched?" Dipper easily finished her sentence, glancing around. The stone door they entered from suddenly slammed shut, revealing another slashed eye carved into it from the other side. The yellow gemstones glowed brighter and brighter, until the entire world around them faded into a grey scale.

 

The twins looked at each-other in the monochrome world, exchanging puzzled looks when they saw they were still in colour.

"This is _weird_ ," Mabel's words sparked an almost instant reaction from their surroundings. The crystals suddenly burst into yellow light once more, and the lights swirled around them madly until a small creature appeared before them.

"Hey, kids!" a cheerful voice shouted at them, its triangular owner in full colour like the twins; an obnoxious yellow much like the crystals. Oddly, the creature wore a black bow tie and a floating top hat, and had long spindly arms and legs. The most unnerving thing about the creature; however; was the single wide eye, the only 'human' feature of the floating triangle.

"Hi?" Mabel replied cautiously, whilst her brother shuffled in front of her instinctively. Mabel had a habit of talking to strangers, which Dipper always felt would cost them both dearly unless he intimidated the strangers to the best of his ability.

The figure didn't appear very intimidated, however, "aren’t-cha gonna say 'hello' too, kiddo?" there was a sense of authority lurking behind the friendly tone, to which Dipper mumbled a dead-panned 'hello' to appease the creature.

"Where are we?" Mabel spoke up again, shifting uncomfortably under the gaze of the single unblinking eye staring her and her brother down.

"Why, the underground, Shooting Star!" it 'spoke' back, and Mabel noticed whenever noise emitted from the figure it glowed in unison with the sound, as did the crystals in the room.

"The underground?" Dipper looked up, wondering how far 'underground' they were from home.

"That's right, you're a smart kid!" the triangle praised, which Dipper shrugged off uncomfortably, "geez, you two must be so confused!"

Mabel relaxed instantly, whilst her twin tensed up, "it's all happened so fast! One moment we were walking and then-!" she was promptly silenced, realising mid-sentence that sound was no longer emitting from her mouth.

"-I bet you're both wondering, 'hm, how do I get out of here?'. Well, look no further, 'cause good ol' Bill Cipher is here to help!" 'Bill' hovered between the twins, his thin clawed hands ghosting on their shoulders.

"Mabel?" Dipper tried to check on Mabel, but Bill turned towards him and hovered in his path.

"As I was saying," the single eye narrowed slightly, as Dipper was rooted to the spot and Mabel clasped her hands over her mouth, "if you want to get through the underground alive, you gotta learn some stuff."

"Like what?" Dipper frowned, still attempting to move from his frozen position. If he was not restrained from movement, he would have jumped back in surprise when the clawed hands reached inside his chest and dragged out a flickering blue light that left him feeling cold.

"This is your soul, kiddo," Bill threw the light into the air, before grabbing it with his claws digging deep into the glowing orb. Dipper winced immediately, "you have one too, Shooting Star, but it would give me a major headache to show you," Bill waved his free hand. Mabel merely watched in horror whilst her brother stared at the flickering light being tossed about.

Bill threw the soul upwards once more, but rather than plummeting to the ground as the twins expected it drifted lazily back towards Dipper, "anyway," Bill nudged it further from its body with his arm, which extended unnaturally, "down here, all sorts of horrible monsters lurk around, and these bad guys can harm your little souls, like _this_ ," he clicked his fingers, and a flurry of triangle-shaped crystals shot up from the ground, piercing the orb. Dipper clutched his chest, unprepared for the damage of his soul having effects.

"Why would you do that?!" he wheezed, and for a moment he caught the eye squint in what appeared to be glee. It quickly turned to a calm neutral look when Dipper made eye contact. The glowing soul before him drifted back into Dipper's chest and the boy took long gasps of air.

"That was pretty terrible," Dipper spoke, mainly to Mabel as a warning.

"Trust me, there's monsters down here that could do far worse, heck, many would be able to knock you kids down with a single physical attack," Bill floated back slightly, as if studying the twins with disdain, "your souls need to get stronger, and to gain strength you must fight back."

"Fight back?" Mabel squeaked, breathing in relief when her voice sounded.

"Yeah, give 'em a slap with your sweater sleeve, whatever!"

Mabel looked down at the sweater in her arms, doubting it could do much damage compared with what she had just witnessed happen to her brother.

"But how can we defend ourselves against... the soul thing?" Dipper frowned, also relieved to find he could move again.

Bill flexed his claws, blue wisps spiralling around each talon, "I'm fond of you guys already, so how about we make a deal? I'm sure I can make some _arrangements_ for you two to survive..." he then held out both hands, each presented to either twin. The crystals around him seemed to glow and extend like spikes, surrounding them. The twins glanced at each-other. Before either could act, a burst of cyan light shot through the yellow and grey, and the twins' eyes snapped open.

 

It could have been nothing more than a bad dream. They were lying in the same area, only the crystals were far less menacing and in place of Bill was a birdlike old man with a band-aid stuck on his long white beard.

"Howdy there, visitors!" he beamed, a wild but seemingly harmless look in his eye, "that darned triangle is always a-botherin' folk in their sleep around here, don't you listen to anythin' that varmint was hootin', ya hear?"

Dipper rubbed his eyes, taking a second look at the man and their surroundings. The old man had taloned feet and hands, white wings attached to his arms and a hooked beak poking out from his beard. He wore a wide-brimmed hat and a pair of overalls that looked as tatty as his head wear. His overall appearance and poor posture reminded Dipper vaguely of a harpy, only with a crazed old man's features rather than a beautiful woman's.

"Who are you?" Mabel asked, rising to her feet.

"Me? I'm," the old man paused, his face crinkling up for a moment in confusion, "old wizard McGucket, that's me! Local caretaker of these here ruins! Nice to be seeing new faces around these parts!" he made a loud shriek into his talons, before offering it as a handshake.

"I'm Mabel!" Mabel shook the talon with no sign of reluctance, not even wincing when the talons locked her hand for a moment, "and my brother is Dipper!"

"Hey," he waved as Mabel's hand was freed by a cheery McGucket.

"This is great!" McGucket beamed, "I can't wait to show you kids around, I've been sprucing up the place with my fireball death cannons! It ain't as effectible as doin' the magic thingamajig but it burns the place down like a pork chop on a barbecue, ehehehe!" he slapped his knee with one of his wings and let out a shrill cackle, one which made the twins eye him with caution. They had no time to react when the old man flapped his wings then hopped through the doorway whilst cackling manically. The only thing left to do, they decided between them, was follow.

 

**Notes for the Chapter:**

> Disclaimer: I had to watch about five videos with McGucket just to get a vague idea on how he talks, and I had no idea how to translate this into writing, results may vary.  
> Also, the fic is going to split into different timelines, now. I won't make it too confusing, though, I hope. Kudos/comments are appreciated, like usual, thanks for reading!
> 
> Unrelated Note: the news about GF ending after season 2 is bittersweet and I'm glad the creators are doing what they want/ending it with grace, but I'm definitely staying in this fandom after the final. Here's hoping others will stay and continue to produce all their awesome content...

**Author's Note:**

> Quick explanation, since I guess I should provide one: this is an AU where characters from Gravity Falls are in the world of Undertale, so this isn't exactly a cross-over. That means Frisk, the skelebros, etc. aren't present (hence why I'm not tagging this as an Undertale fic; though I might write some fics for that fandom one day), also the story will loosely follow the events of Undertale but not ENTIRELY, so even if you know the plot of Undertale this (hopefully) shouldn't be too predictable, aha. Anyway, thanks for reading, should be more to come soon!


End file.
